Classifications

• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
  • C08G63/91—Polymers modified by chemical after-treatment
  • C08G63/914—Polymers modified by chemical after-treatment derived from polycarboxylic acids and polyhydroxy compounds
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08G—MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONS ONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS
  • C08G63/00—Macromolecular compounds obtained by reactions forming a carboxylic ester link in the main chain of the macromolecule
  • C08G63/66—Polyesters containing oxygen in the form of ether groups
  • C08G63/668—Polyesters containing oxygen in the form of ether groups derived from polycarboxylic acids and polyhydroxy compounds
  • C08G63/672—Dicarboxylic acids and dihydroxy compounds

Definitions

• the present invention relates to biodegradable polyether esters obtained by reacting a bisoxazoline C1 with a polyether ester such as P1 obtainable by reacting a mixture essentially comprising
• n 2, 3 or 4 and m is an integer from 2 to 250, or mixtures thereof,
• the molar ratio of (a1) to (a2) is chosen in the range from 0.4:1 to 1.5:1, with the proviso that the polyether ester P1 has a molecular weight (M n ) in the range from 5000 to 80,000 g/mol, a viscosity number in the range from 30 to 450 g/ml (measured in o-dichlorobenzene/phenol (50/50 ratio by weight) at a concentration of 0.5% by weight of polyether ester P1 at 25° C.) and a melting point in the range from 50 to 200° C., and with the further proviso that from 0 to 5 mol%, based on the molar quantity of component (a1) employed, of a compound D with at least three groups capable of ester formation are employed to prepare the polyether ester P1, and the further proviso that the polyether ester P1 has both hydroxyl and carboxyl end groups, with the molar ratio of carboxyl end groups to hydroxyl end groups being chosen to
• the invention furthermore relates to polymers and biodegradable thermoplastic molding compositions as claimed in the dependent claims, processes for the preparation thereof, the use thereof for producing biodegradable moldings and adhesives, biodegradable moldings, foams and blends with starch obtainable from the polymers and molding compositions according to the invention.
• Polymers which are biodegradable, ie. decompose under environmental influences in an appropriate and demonstrable time span have been known for some time. This degradation usually takes place by hydrolysis and/or oxidation, but predominantly by the action of microorganisms such as bacteria, yeasts, fungi and algae.
• Y. Tokiwa and T. Suzuki describe the enzymatic degradation of aliphatic polyesters, for example including polyesters based on succinic acid and aliphatic diols.
• EP-A 565,235 describes aliphatic copolyesters containing --NH--C(O)O--! groups (urethane units).
• the copolyesters of EP-A 565,235 are obtained by reacting a prepolyester, which is obtained by reacting essentially succinic acid and an aliphatic diol, with a diisocyanate, preferably hexamethylene diisocyanate.
• the reaction with the diisocyanate is necessary according to EP-A 565,235 because the polycondensation alone results only in polymers with molecular weights such that they display unsatisfactory mechanical properties.
• a crucial disadvantage is the use of succinic acid or ester derivatives thereof to prepare the copolyesters because succinic acid and derivatives thereof are costly and are not available in adequate quantity on the market.
• the polyesters prepared using succinic acid as the only acid component are degraded only extremely slowly.
• WO 92/13020 discloses copolyether esters based on predominantly aromatic dicarboxylic acids, short-chain ether diol segments such as diethylene glycol, long-chain polyalkylene glycols such as polyethylene glycol (PEG) and aliphatic diols, where at least 85 mol% of the polyester diol residue comprise a terephthalic acid residue.
• the hydrophilicity of the copolyester can be increased and the crystallinity can be reduced by modifications such as incorporation of up to 2.5 mol% of metal salts of 5-sulfoisophthalic acid.
• This is said in WO 92/13020 to make the copolyesters biodegradable.
• a disadvantage of these copolyesters is that biodegradation by microorganisms was not demonstrated, on the contrary only the behavior towards hydrolysis in boiling water was carried out.
• polyesters which are essentially composed of aromatic dicarboxylic acid units and aliphatic diols, such as PET (polyethylene terephthalate) and PBT (polybutylene terephthalate), are not enzymatically degradable.
• PET polyethylene terephthalate
• PBT polybutylene terephthalate
• copolyesters and copolyether esters which contain blocks composed of aromatic dicarboxylic acid units and aliphatic diols or ether diols.
• the intention was, in particular, that the polymers according to the invention be preparable from known and low-cost monomer units and be insoluble in water. It was furthermore the intention that it be possible to obtain products tailored for the desired uses according to the invention by specific modifications such as chain extension, incorporation of hydrophilic groups and groups having a branching action.
• the polyether esters P1 according to the invention have a molecular weight (M n ) in the range from 5000 to 80,000, preferably from 6000 to 45,000, particularly preferably from 8000 to 35,000, g/mol, a viscosity number in the range from 30 to 450, preferably from 50 to 400, g/ml (measured in o-dichlorobenzene/phenol (50/50 ratio by weight) at a concentration of 0.5% by weight of polyether ester P1 at 25° C.) and a melting point in the range from 50 to 200, preferably from 60 to 160, ° C., and the further proviso that the polyether ester P1 has both hydroxyl and carboxyl end groups, with the molar ratio of carboxyl end groups to hydroxyl end groups being chosen to be greater than one, preferably greater than two.
• M n molecular weight
• the polyether esters P1 are obtained according to the invention by reacting a mixture essentially comprising
• adipic acid or ester-forming derivatives thereof in particular the di-C 1 -C 6 -alkyl esters such as dimethyl, diethyl, dipropyl, dibutyl, diisobutyl, dipentyl and dihexyl adipate, or mixtures thereof, preferably adipic acid and dimethyl adipate, or mixtures thereof,
• terephthalic acid or ester-forming derivatives thereof in particular the di-C 1 -C 6 -alkyl esters such as dimethyl, diethyl, dipropyl, dibutyl, dipentyl or dihexyl terephthalate, or mixtures thereof, preferably terephthalic acid and dimethyl terephthalate, or mixtures thereof, and
• n 2, 3 or 4, preferably two and three, particularly preferably two, and m is an integer from 2 to 250, preferably from 5 two to 100, or mixtures thereof,
• molar ratio of (a1) to (a2) is chosen in the range from 0.4:1 to 1.5:1, preferably from 0.6:1 to 1.25:1.
• the compound containing sulfonate groups which is normally employed is an alkali metal or alkaline earth metal salt of a dicarboxylic acid containing sulfonate groups, or the ester-forming derivatives thereof, preferably alkali metal salts of 5-sulfoisophthalic acid or mixtures thereof, particularly preferably the sodium salt.
• the dihydroxy compounds (a21) employed according to the invention are selected from the group consisting of C 2 -C 6 -alkanediols and C 5 -C 10 -cycloalkanediols, such as ethylene glycol, 1,2- and 1,3-propanediol, 1,2- and 1,4-butanediol, 1,5-pentanediol or 1,6-hexanediol, in particular ethylene glycol, 1,3-propanediol and 1,4-butanediol, cyclopentanediol, cyclohexanediol, 1,2-cyclohexanedimethanol, 1,4-cyclohexanedimethanol, particularly preferably ethylene glycol and 1,4-butanediol, and mixtures thereof.
• C 2 -C 6 -alkanediols and C 5 -C 10 -cycloalkanediols such
• the molecular weight (M n ) of the polyethylene glycol is usually chosen in the range from 250 to 8000, preferably from 600 to 3000, g/mol.
• the compounds D preferably contain three to ten functional groups capable of forming ester linkages. Particularly preferred compounds D have three to six functional groups of this type in the molecule, in particular three to six hydroxyl groups and/or carboxyl groups. Examples which may be mentioned are:
• the compound D it is possible, for example, to alter the melt viscosity in a desired manner, to increase the impact strength and to reduce the crystallinity of the polymers or molding compositions according to the invention.
• biodegradable polyether esters P1 The preparation of the biodegradable polyether esters P1 is known in principle (Sorensen and Campbell, Preparative Methods of Polymer Chemistry, Interscience Publishers, Inc., New York, 1961, pages 111-127; Encycl. of Polym. Science and Eng., Vol. 12, 2nd Edition, John Wiley & Sons, 1988, pages 75-117; Kunststoff-Handbuch, Volume 3/1, Carl Hanser Verlag, Kunststoff, 1992, pages 15-23 (Preparation of Polyesters); WO 92/13020; EP-A 568,593; EP-A 565,235; EP-A 28,687) so that details on this are superfluous.
• reaction of dimethyl esters of component (a1) with component (a2) can be carried out at from 160 to 230° C. in the melt under atmospheric pressure, advantageously under an inert gas atmosphere.
• component (a2) relative to component (a1), for example up to 21/2 times, preferably up to 1.67 times.
• the biodegradable polyether ester P1 is normally prepared with addition of suitable conventional catalysts such as metal compounds based on the following elements such as Ti, Ge, Zn, Fe, Mn, Co, Zr, V, Ir, La, Ce, Li, and Ca, preferably organometallic compounds based on these metals, such as salts of organic acids, alkoxides, acetylacetonates and the like, particularly preferably based on zinc, tin and titanium.
• suitable conventional catalysts such as metal compounds based on the following elements such as Ti, Ge, Zn, Fe, Mn, Co, Zr, V, Ir, La, Ce, Li, and Ca, preferably organometallic compounds based on these metals, such as salts of organic acids, alkoxides, acetylacetonates and the like, particularly preferably based on zinc, tin and titanium.
• esterification thereof with component (a2) can take place before, at the same time as or after the transesterifidation.
• the process described in DE-A 23 26 026 for preparing modified polyalkylene terephthalates can be used.
• the polycondensation is carried out as far as the desired molecular weight, taking account of the molar ratio of carboxyl end groups to hydroxyl end groups, which is chosen to be greater than one, preferably greater than 2, as a rule under reduced pressure or in a stream of inert gas, for example of nitrogen, with further heating to from 180 to 260° C.
• the desired end-group ratio can be adjusted
• polyfunctional carboxylic acids or derivatives thereof preferably dicarboxylic anhydrides such as succinic anhydride, phthalic anhydride, pyromellitic anhydride or trimellitic anhydride, if the polyether ester P1 predominantly has hydroxyl end groups owing to use of an excess of component a2.
• dicarboxylic anhydrides such as succinic anhydride, phthalic anhydride, pyromellitic anhydride or trimellitic anhydride
• stabilizers In order to prevent unwanted degradation and/or side reactions, it is also possible in this stage of the process if required to add stabilizers (see EP-A 21 042 and U.S. Pat. No. 4,321,341).
• stabilizers are the phosphorus compounds described in EP-A 13 461, U.S. Pat. No. 4,328,049 or in B. Fortunato et al., Polymer Vol. No. 18, pages 4006-4010, 1994, Butterworth-Heinemann Ltd. These may also in some cases act as inactivators of the catalysts described above. Examples which may be mentioned are: organophosphites, phosphonous acid and phosphorous acid.
• Examples of compounds which act only as stabilizers are: trialkyl phosphites, triphenyl phosphite, trialkyl phosphates, triphenyl phosphate and tocopherol (obtainable as Uvinul® 2003AO (BASF) for example).
• biodegradable copolymers according to the invention for example in the packaging sector, eg. for foodstuffs, it is as a rule desirable to select the lowest possible content of catalyst employed and not to employ any toxic compounds.
• titanium and zinc compounds are non-toxic as a rule (Sax Toxic Substance Data Book, Shizuo Fujiyama, Maruzen, K. K., 360 S. (cited in EP-A 565,235), see also Rompp Chemie Lexikon Vol. 6, Thieme Verlag, Stuttgart, New York, 9th Edition, 1992, pages 4626-4633 and 5136-5143). Examples which may be mentioned are: dibutoxydiacetoacetoxytitanium, tetrabutyl orthotitanate and zinc(II) acetate.
• the ratio by weight of catalyst to biodegradable polyether ester P1 is normally in the range from 0.01:100 to 3:100, preferably from 0.05:100 to 2:100, it also being possible to employ smaller quantities, such as 0.0001:100, in the case of highly active titanium compounds.
• the catalyst can be employed right at the start of the reaction, directly shortly before the removal of the excess diol or, if required, also distributed in a plurality of portions during the preparation of the biodegradable polyether esters P1. It is also possible if required to employ different catalysts or mixtures thereof.
• the biodegradable polyether esters P2 according to the invention have a molecular weight (M n ) in the range from 5000 to 80,000, preferably from 6000 to 45,000, particularly preferably from 10,000 to 40,000, g/mol, a viscosity number in the range from 30 to 450, preferably from 50 to 400, g/ml (measured in o-dichlorobenzene/phenol (50/50 ratio by weight) at a concentration of 0.5% by weight of polyether ester P2 at 25° C.) and a melting point in the range from 50 to 235, preferably from 60 to 235, ° C., and have both hydroxyl and carboxyl end groups, with the molar ratio of carboxyl end groups to hydroxyl end groups being chosen to be greater than one, preferably greater than two.
• M n molecular weight in the range from 5000 to 80,000, preferably from 6000 to 45,000, particularly preferably from 10,000 to 40,000, g/mol, a viscos
• biodegradable polyether esters P2 are obtained according to the invention by reacting a mixture essentially comprising
• 5-80 preferably from 20 to 75, particularly preferably from 30 to 70, mol% of terephthalic acid or ester-forming derivatives thereof or mixtures thereof, and
• component (b3) from 0.01 to 100, preferably from 0.1 to 80, % by weight, based on component (b1), of a hydroxy carboxylic acid B1, and
• hydroxy carboxylic acid B1 is defined by the formulae IIa or IIb ##STR1## where p is an integer from 1 to 1500, preferably from 1 to 1000, and r is 1, 2, 3 or 4, preferably 1 and 2, and G is a radical selected from the group consisting of phenylene, --(CH 2 ) k --, where k is an integer from 1, 2, 3, 4 or 5, preferably 1 and 5, --C(R)H-- and --C(R)HCH 2 , where R is methyl or ethyl.
• biodegradable polyether esters P2 are expediently prepared in a similar way to the preparation of the polyether esters P1, it being possible to add the hydroxy carboxylic acid B1 both at the start of the reaction and after the esterification or transesterification stage.
• the hydroxy carboxylic acid B1 such as glycolic acid, D-, L- or D,L-lactic acid, 6-hydroxyhexanoic acid, the cyclic derivatives thereof such as glycolide (1,4-dioxane-2,5-dione), D- or L-dilactide (3,6-dimethyl-1,4-dioxane-2,5-dione), p-hydroxybenzoic acid and oligomers and polymers such as poly-3-hydroxybutyric acid, polyhydroxyvaleric acid, polylactide (obtainable as EcoPLA® (from Cargill) for example) and a mixture of poly-3-hydroxybutyric acid and polyhydroxyvaleric acid (obtainable under the name Biopol® from Zeneca for example), the low molecular weight and cyclic derivatives thereof are particularly preferably employed for preparing polyether esters P2.
• the cyclic derivatives thereof such as glycolide (1,4-dioxane-2,5-dione), D- or L-
• the biodegradable polyether esters Q1 according to the invention have a molecular weight (M n ) in the range from 5000 to 100,000, preferably from 8000 to 80,000, a viscosity number in the range from 30 to 450, preferably from 50 to 400 g/ml (measured in o-dichlorobenzene/phenol (50/50 ratio by weight) at a concentration of 0.5% by weight of polyether ester Q1 at 25° C.), and a melting point in the range from 50 to 235, preferably from 60 to 235, ° C., and have both hydroxyl and carboxyl end groups, with the molar ratio of carboxyl end groups to hydroxyl end groups being chosen to be greater than one, preferably greater than two.
• M n molecular weight
• the polyether esters Q1 are obtained according to the invention by reacting a mixture essentially comprising
• reaction of the polyether esters P1 with the hydroxy carboxylic acid B1, if required in the presence of compound D, preferably takes place in the melt at from 120 to 260° C. under an inert gas atmosphere, if desired also under reduced pressure.
• the procedure can be both batchwise and continuous, for example in stirred vessels or (reaction) extruders.
• reaction rate can, if required, be increased by adding conventional transesterification catalysts (see those described hereinbefore for the preparation of the polyether esters P1).
• a preferred embodiment relates to polyether esters Q1 with block structures formed from components P1 and B1: when cyclic derivatives of B1 (compounds IIb) are used it is possible in the reaction with the biodegradable polyether ester P1 to obtain, by a ring-opening polymerization initiated by the end groups of P1, in a conventional way polyether esters Q1 with block structures (on the ring-opening polymerization, see Encycl. of Polym. Science and Eng. Volume 12, 2nd Edition, John Wiley & Sons, 1988, pages 1-75, in particular pages 36-41).
• reaction can, if required, be carried out with addition of conventional catalysts like the transesterification catalysts described hereinbefore, and tin octanoate is particularly preferred (see also Encycl. of Polym. Science and Eng. Volume 12, 2nd Edition, John Wiley & Sons, 1988, pages 1-75, in particular pages 36-41).
• the biodegradable polyether esters Q2 according to the invention have a molecular weight (M n ) in the range from 6000 to 80,000, preferably from 8000 to 50,000, particularly preferably from 10,000 to 40,000, g/mol, a viscosity number in the range from 30 to 450, preferably from 50 to 400, g/ml (measured in o-dichlorobenzene/phenol (50/50 ratio by weight) at a concentration of 0.5% by weight of polyether ester Q2 at 25° C.), and a melting point in the range from 50 to 200° C., preferably from 60 to 160° C., and have both hydroxyl and carboxyl end groups, with the molar ratio of carboxyl end groups to hydroxyl end groups being chosen to be greater than one, preferably greater than two.
• M n molecular weight in the range from 6000 to 80,000, preferably from 8000 to 50,000, particularly preferably from 10,000 to 40,000, g/mol, a viscosity
• the polyether esters Q2 are obtained according to the invention by reacting a mixture essentially comprising
• bisoxazolines C1 all conventional bisoxazolines can be used as bisoxazolines C1.
• Appropriate bisoxazolines are described, for example, in DE-A 39 15 874 (commercially available under the name Loxamid®). Further bisoxazolines are described in WO 94/03523 (PCT/EP 93/01986).
• Particularly preferred bisoxazolines C1 are bisoxazolines of the general formula III ##STR2##
• the bisoxazolines C1 of the general formula III are generally obtainable by the process of Angew. Chem. Int. Edit. 11 (1972), 287-288.
• bisoxazolines which may be mentioned are 2,2'-bis(2-oxazoline), bis(2-oxazolinyl)methane, 1,2-bis(2-oxazolinyl)ethane, 1,3-bis(2-oxazolinyl)propane, 1,4-bis(2-oxazolinyl)butane, 1,4-bis(2-oxazolinyl)benzene, 1,2-bis(2-oxazolinyl)benzene and 1,3-bis(2-oxazolinyl)benzene.
• the polyether esters P1 are reacted with the bisoxazoline C1 preferably in the melt (see also: J. Appl. Polym. Science, 33 (1987) 3069-3079), it being necessary to take care that, if possible, no side reactions which may lead to crosslinking or gel formation occur.
• the reaction is normally carried out at from 120 to 260, preferably from 130 to 240, particularly preferably 140-220, ° C., with the addition of the bisoxazoline advantageously taking place in a plurality of portions or continuously.
• reaction of the polyether ester P1 with the bisoxazoline C1 in the presence of conventional inert solvents such as toluene, methyl ethyl ketone or dimethylformamide (DMF) or mixtures thereof, in which case the reaction is as a rule carried out at from 80 to 200, preferably from 90 to 150, ° C.
• inert solvents such as toluene, methyl ethyl ketone or dimethylformamide (DMF) or mixtures thereof, in which case the reaction is as a rule carried out at from 80 to 200, preferably from 90 to 150, ° C.
• the reaction with the bisoxazoline C1 can be carried out batchwise or continuously, for example in stirred vessels, reaction extruders or through mixing heads.
• the reaction can also be carried out at molar ratios of from 1:3 to 1.5:1 without technical problems.
• a dicarboxylic acid preferably selected from the group consisting of adipic acid, succinic acid, terephthalic acid and isophthalic acid.
• the biodegradable polymers T1 according to the invention have a molecular weight (M n ) in the range from 10,000 to 100,000, preferably from 11,000 to 80,000, preferably from 11,000 to 50,000, g/mol, a viscosity number in the range from 30 to 450, preferably from 50 to 400, g/ml (measured in o-dichlorobenzene/phenol (50/50 ratio by weight) at a concentration of 0.5% by weight of polymer T1 at 25° C.) and a melting point in the range from 50 to 235, preferably from 60 to 235, ° C.
• M n molecular weight
• biodegradable polymers T1 are obtained according to the invention by reacting a polyether ester Q1 as claimed in claim 3 with
• reaction is, as a rule, carried out in a similar way to the preparation of the polyether esters Q2.
• the biodegradable polymers T2 according to the invention have a molecular weight (M n ) in the range from 10,000 to 100,000, preferably from 11,000 to 80,000, particularly preferably from 11,000 to 50,000, g/mol, a viscosity number in the range from 30 to 450, preferably from 50 to 400, g/ml (measured in o-dichlorobenzene/phenol (50/50 ratio by weight) at a concentration of 0.5% by weight of polymer T2 at 25° C.) and a melting point in the range from 50 to 235, preferably from 60 to 235, ° C.
• M n molecular weight
• biodegradable polymers T2 are obtainable according to the invention by reacting the polyether ester Q2 with
• the biodegradable polymers T3 according to the invention have a molecular weight (M n ) in the range from 10,000 to 100,000, preferably from 11,000 to 80,000 g/mol, a viscosity number in the range from 30 to 450, preferably from 50 to 400, g/ml (measured in o-dichlorobenzene/phenol (50/50 ratio by weight) at a concentration of 0.5% by weight of polymer T3 at 25° C.) and a melting point in the range from 50 to 235, preferably from 60 to 235, ° C.
• M n molecular weight
• the biodegradable polymers T3 are obtained according to the invention by reacting (g1) polyether ester P2, or (g2) a mixture essentially comprising polyether ester P1 and 0.01-50, preferably from 0.1 to 40, % by weight, based on the polyether ester P1, of hydroxy carboxylic acid B1, or (g3) a mixture essentially comprising polyether esters P1 which differ from one another in composition, with
• polyether esters P2 whose repeating units are randomly distributed in the molecule are employed.
• polyether esters P2 whose polymer chains have block structures.
• Polyether esters P2 of this type can generally be obtained by appropriate choice, in particular of the molecular weight, of the hydroxy carboxylic acid B1.
• the reaction can also be carried out in solution using the solvents mentioned for the preparation of the polymers T1 from the polyether esters Q1 and the bisoxazolines C1.
• thermoplastic molding compositions T4 are obtained according to the invention by mixing in a conventional way, preferably with the addition of conventional additives such as stabilizers, processing aids, fillers etc. (see J. of Appl. Polym. Sci., 32 (1986) 6191-6207; WO 92/0441; EP 515,203; Kunststoff-Handbuch, Vol. 3/1, Carl Hanser Verlag Kunststoff, 1992, pages 24-28)
• high molecular weight hydroxy carboxylic acids B1 such as polycaprolactone or polylactide (eg. EcoPLA®) or polyglycolide or polyhydroxyalkanoates such as poly-3-hydroxybutyric acid, polyhydroxyvaleric acid and mixtures thereof (eg. Biopol®) with a molecular weight (M n ) in the range from 10,000 to 150,000, preferably from 10,000 to 100,000, g/mol are employed.
• WO 92/0441 and EP-A 515 203 disclose that high molecular weight polylactide without added plasticizers is too brittle for most applications. It is possible in a preferred embodiment to prepare a blend starting from 0.5-20, preferably from 0.5 to 10, % by weight of polyether ester P1 as claimed in claim 1 or polyether ester Q2 as claimed in claim 4 and 99.5-80, preferably from 99.5 to 90, % by weight of polylactide, which displays a distinct improvement in the mechanical properties, for example an increase in the impact strength, compared with pure polylactide.
• Another preferred embodiment relates to a blend obtainable by mixing from 99.5 to 40, preferably from 99.5 to 60, % by weight of polyether ester P1 as claimed in claim 1 or polyether ester Q2 as claimed in claim 4 and from 0.5 to 60, preferably from 0.5 to 40, % by weight of a high molecular weight hydroxy carboxylic acid B1, particularly preferably polylactide (eg. EcoPLA®), polyglycolide, poly-3-hydroxybutyric acid, polyhydroxyvaleric acid and mixtures thereof (eg. Biopol®), and polycaprolactone. Blends of this type are completely biodegradable and, according to observations to date, have very good mechanical properties.
• polylactide eg. EcoPLA®
• thermoplastic molding compositions T4 according to the invention are preferably obtained by observing short mixing times, for example when carrying out the mixing in an extruder. It is also possible to obtain molding compositions which have predominantly blend structures by choice of the mixing parameters, in particular the mixing time and, if required, the use of inactivators, ie. it is possible to control the mixing process so that transesterification reactions can also take place at least partly.
• adipic acid or the ester-forming derivatives thereof or the mixtures thereof with at least one other aliphatic C 4 -C 10 - or cycloaliphatic C 5 -C 10 -dicarboxylic acid or dimer fatty acid such as succinic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid or sebacic acid or an ester derivative such as the di-C 1 -C 6 -alkyl esters thereof or the anhydrides thereof such as succinic anhydride, or mixtures thereof, preferably succinic acid, succinic anhydride, sebacic acid, dimer fatty acid and di-C 1 -C 6 -alkyl esters such as dimethyl, diethyl, di-n-propyl, diisobutyl, di-n-pentyl, dineopentyl, di-n-hexyl esters
• a particularly preferred embodiment relates to the use as component (a1) of the mixture, described in EP-A 7445, of succinic acid, adipic acid and glutaric acid and the C 1 -C 6 -alkyl esters thereof such as dimethyl, diethyl, di-n-propyl, diisobutyl, di-n-pentyl, dineopentyl, di-n-hexyl esters, especially the dimethyl esters and diisobutyl esters thereof.
• terephthalic acid or the ester-forming derivatives thereof, or the mixtures thereof with at least one other aromatic dicarboxylic acid such as isophthalic acid, phthalic acid or 2,6-naphthalenedicarboxylic acid, preferably isophthalic acid, or an ester derivative such as a di-C 1 -C 6 -alkyl ester such as dimethyl, diethyl, di-n-propyl, diisobutyl, di-n-pentyl, dineopentyl, di-n-hexyl ester, in particular a dimethyl ester, or mixtures thereof.
• aromatic dicarboxylic acid such as isophthalic acid, phthalic acid or 2,6-naphthalenedicarboxylic acid, preferably isophthalic acid, or an ester derivative such as a di-C 1 -C 6 -alkyl ester such as dimethyl, diethyl, di-n-propyl, diisobutyl, di-n
• the polymers according to the invention can be applied to coating substrates by rolling, spreading, spraying or pouring.
• Preferred coating substrates are those which are compostable or rot such as moldings of paper, cellulose or starch.
• the polymers according to the invention can also be used to produce moldings which are compostable. Moldings which may be mentioned by way of example are: disposable articles such as crockery, cutlery, refuse sacks, sheets for agriculture to advance harvesting, packaging sheets and vessels for growing plants.
• the threads can, if required, be stretched, stretch-twisted, stretch-wound, stretch-warped, stretch-sized and stretch-texturized by customary methods.
• the stretching to flat yarn can moreover take place in the same working step (fully drawn yarn or fully oriented yarn) or in a separate step.
• the stretch warping, stretch sizing and stretch texturizing are generally carried out in a working step separate from the spinning.
• the threads can be further processed to fibers in a conventional way. Sheet-like structures can then be obtained from the fibers by weaving or knitting.
• the moldings, coating compositions and threads etc. described above can, if required, also contain fillers which can be incorporated during the polymerization process at any stage or subsequently, for example in a melt of the polymers according to the invention.
• fillers based on the polymers according to the invention.
• suitable fillers are carbon black, starch, lignin powder, cellulose fibers, natural fibers such as sisal and hemp, iron oxides, clay minerals, ores, calcium carbonate, calcium sulfate, barium sulfate and titanium dioxide.
• the fillers can in some cases also contain stabilizers such as tocopherol (vitamin E), organic phosphorus compounds, mono-, di- and polyphenols, hydroquinones, diarylamines, thioethers, UV stabilizers, nucleating agents such as talc, and lubricants and mold release agents based on hydrocarbons, fatty alcohols, higher carboxylic acids, metal salts of higher carboxylic acids such as calcium and zinc stearate, and montan waxes.
• stabilizers such as tocopherol (vitamin E), organic phosphorus compounds, mono-, di- and polyphenols, hydroquinones, diarylamines, thioethers, UV stabilizers, nucleating agents such as talc, and lubricants and mold release agents based on hydrocarbons, fatty alcohols, higher carboxylic acids, metal salts of higher carboxylic acids such as calcium and zinc stearate, and montan waxes.
• Such stabilizers etc. are described in detail in Kunststoff-Hand
• the polymers according to the invention can additionally be colored in any desired way by adding organic or inorganic dyes.
• the dyes can also in the widest sense be regarded as filler.
• a particular application of the polymers according to the invention relates to the use as compostable sheet or a compostable coating as outer layer of diapers.
• the outer layer of the diapers effectively prevents penetration by liquids which are absorbed inside the diaper by the fluff and superabsorbers, preferably by biodegradable superabsorbers, for example based on crosslinked polyacrylic acid or crosslinked polyacrylamide. It is possible to use a web of a cellulose material as inner layer of the diaper.
• the outer layer of the described diapers is biodegradable and thus compostable. It disintegrates on composting so that the entire diaper rots, whereas diapers provided with an outer layer of, for example, polyethylene cannot be composted without previous reduction in size or elaborate removal of the polyethylene sheet.
• polymers and molding compositions according to the invention relate to the production of adhesives in a conventional way (see, for example, Encycl. of Polym. Sc. and Eng. Vol.1, "Adhesive Compositions", pages 547-577).
• the polymers and molding compositions according to the invention can also be processed as disclosed in EP-A 21 042 using suitable tackifying thermoplastic resins, preferably natural resins, by the methods described therein.
• the polymers and molding compositions according to the invention can also be further processed as disclosed in DE-A 4 234 305 to solvent-free adhesive systems such as hot melt sheets.
• Another preferred application relates to the production of completely degradable blends with starch mixtures (preferably with thermoplastic starch as described in WO 90/05161) in a similar process to that described in DE-A 42 37 535.
• the polymers and thermoplastic molding compositions according to the invention can, according to observations to date, because of their hydrophobic nature, their mechanical properties, their complete biodegradability, their good compatibility with thermoplastic starch and not least because of their favorable raw material basis, advantageously be employed as synthetic blend component.
• Another use of the polymers and molding compositions according to the invention relates to the production of foams, generally by conventional methods (see EP-A 372,846; Handbook of Polymeric foams and Foam Technology, Hanser Publisher, Kunststoff, 1991, pages 375-408).
• compound D preferably pyromellitic dianhydride and trimellitic anhydride
• the advantages of the polymers according to the invention over known biodegradable polymers are a favorable raw material basis with readily available starting materials such as adipic acid, terephthalic acid and conventional diols, interesting mechanical properties due to the combination of "hard” (owing to the aromatic dicarboxylic acids such as terephthalic acid) and “soft” (owing to the aliphatic dicarboxylic acids such as adipic acid) segments in the polymer chain and the variation in uses due to simple modifications, a satisfactory degradation by microorganisms, especially in compost and soil, and a certain resistance to microorganisms in aqueous systems at room temperature, which is particularly advantageous for many applications.
• the random incorporation of the aromatic dicarboxylic acids of components (a1) in various polymers makes the biological attack possible and thus achieves the desired biodegradability.
• a particular advantage of the polymers according to the invention is that it is possible by tailoring the formulations to optimize both the biodegradation and the mechanical properties for the particular application.
• the polymers were cooled with liquid nitrogen or dry ice and finely ground in a mill (the rate of enzymatic degradation increases with the surface area of the ground material).
• 30 mg of finely ground polymer powder and 2 ml of a 20 mmol/l aqueous K 2 HPO 4 /KH 2 PO 4 buffer solution (pH: 7.0) were placed in an Eppendorf tube (2 ml) and equilibrated on a rotator at 37° C. for 3 h. Subsequently 100 units of lipase from either Rhizopus arrhizus, Rhizopus delemar or Pseudomonas pl.
• ⁇ DOC values (DOC(sample+enzyme)-DOC(enzyme control)-DOC(blank)) found can be regarded as a measure of the enzymatic degradability of the samples. They are shown in each case comparing with a measurement with powdered polycaprolactone® Tone P 787 (Union Carbide). It should be noted in the assessment that these are not absolutely quantifiable data. The connection between the surface area of the ground material and the rate of enzymatic degradation has been pointed out above. Furthermore, the enzyme activities may also vary.
• hydroxyl number OH number
• acid number AN
• test was repeated without test substance (blank sample).
• V1 ml of standard solution used with test substance
• V2 ml of standard solution used without test substance.
• acetylation reagent 810 ml of pyridine, 100 ml of acetic anhydride and 9 ml of acetic acid
• test substance About 1 to 1.5 g of test substance were accurately weighed and mixed with 10 ml of toluene and 10 ml of pyridine and then heated to 95° C. After a solution was obtained it was cooled to room temperature, 5 ml of water and 50 ml of THF were added, and titration was carried out with 0.1 N standard ethanolic KOH solution.
• V1 ml of standard solution used with test substance
• V2 ml of standard solution used without test substance.
• the OH number is obtained from the sum of the apparent OH number and the AN:
• PCL polycaprolactone Tone P 787 (Union Carbide)
• VN viscosity number (measured in o-dichlorobenzene/phenol (50/50 ratio by weight) at a concentration of 0.5% by weight of polymer at 25° C.)
• T m melting temperature
• T g glass transition temperature (midpoint of the DSC plots)
• the DSC measurements were carried out with a DuPont 912 + thermal analyzer 990 DSC apparatus.
• the temperature and enthalpy calibration took place in a conventional way.
• the sample weight was typically 13 mg.
• the heating and cooling rates were, unless otherwise noted, 20 K/min.
• the samples were measured under the following conditions: 1. heating run on samples in the state as supplied, 2. rapid cooling from the melt, 3. heating run on samples cooled from the melt (samples from 2).
• the second DSC runs in each case allowed comparison between the different samples after a uniform thermal history.

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• Chemical & Material Sciences (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Medicinal Chemistry (AREA)
• Polymers & Plastics (AREA)
• Organic Chemistry (AREA)
• General Chemical & Material Sciences (AREA)
• Polyesters Or Polycarbonates (AREA)
• Biological Depolymerization Polymers (AREA)
• Compositions Of Macromolecular Compounds (AREA)
• Adhesives Or Adhesive Processes (AREA)
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• 1996
  • 1996-02-03 AU AU47179/96A patent/AU4717996A/en not_active Abandoned
  • 1996-02-03 AU AU47870/96A patent/AU4787096A/en not_active Abandoned
  • 1996-02-03 US US08/894,240 patent/US5936045A/en not_active Expired - Lifetime
  • 1996-02-03 JP JP52462196A patent/JP3452583B2/ja not_active Expired - Fee Related
  • 1996-02-03 DE DE59600710T patent/DE59600710D1/de not_active Expired - Lifetime
  • 1996-02-03 DK DK96902980T patent/DK0809666T4/da active
  • 1996-02-03 ES ES96902980T patent/ES2122792T5/es not_active Expired - Lifetime
• 1997
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  • 1997-08-15 NO NO19973767A patent/NO315203B1/no not_active IP Right Cessation
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